<template>
    <!-- 商品分类导航 -->
    <div class="type-nav">
        <div class="container">
            <div @mouseenter="enterShow" @mouseleave="leaveShow">
                <h2 class="all">全部商品分类</h2>
                <!--过度动画-->
                <transition name="sort">
                    <!--三级联动-->
                    <div class="sort" v-show="show">
                        <!--利用事件的委派+编程式导航实现路由的跳转与传递参数-->
                        <div class="all-sort-list2" @click="goSearch">
                            <!--一级-->
                            <div
                                class="item"
                                v-for="(c1, index) in categoryList"
                                :key="c1.categoryId"
                                @mouseenter="changeIndex(index)"
                                :class="{cur: currentIndex === index}"
                            >
                                <h3>
                                    <a :data-categoryName="c1.categoryName" :data-category1Id="c1.categoryId">
                                        {{ c1.categoryName }}
                                    </a>
                                </h3>
                                <!--二级-->
                                <div
                                    class="item-list clearfix"
                                    :style="{display: currentIndex === index ? 'block' : 'none'}"
                                >
                                    <div class="subitem" v-for="c2 in c1.categoryChild" :key="c2.categoryId">
                                        <dl class="fore">
                                            <dt>
                                                <a
                                                    :data-categoryName="c2.categoryName"
                                                    :data-category2Id="c2.categoryId"
                                                >
                                                    {{ c2.categoryName }}
                                                </a>
                                            </dt>
                                            <!--三级-->
                                            <dd>
                                                <em v-for="c3 in c2.categoryChild" :key="c3.categoryId">
                                                    <a
                                                        :data-categoryName="c3.categoryName"
                                                        :data-category3Id="c3.categoryId"
                                                    >
                                                        {{ c3.categoryName }}
                                                    </a>
                                                </em>
                                            </dd>
                                        </dl>
                                    </div>
                                </div>
                            </div>
                        </div>
                    </div>
                </transition>
            </div>
            <nav class="nav">
                <a href="javascript:">服装城</a>
                <a href="javascript:">美妆馆</a>
                <a href="javascript:">优选购超市</a>
                <a href="javascript:">全球购</a>
                <a href="javascript:">闪购</a>
                <a href="javascript:">团购</a>
                <a href="javascript:">有趣</a>
                <a href="javascript:">秒杀</a>
            </nav>
        </div>
    </div>
</template>

<script setup lang="ts">
import {ref, computed, onMounted} from 'vue'
import {LocationQueryRaw, RouteLocationNamedRaw, useRoute, useRouter} from 'vue-router'
import {useHomeStore} from '@/store'
import throttle from 'lodash/throttle'

const store = useHomeStore()
const route = useRoute()
const router = useRouter()

//当前这个属性决定了到底那个h3身上有类名
const currentIndex = ref(-1)
//是否显示TypeNav
const show = ref(true)
const categoryList = computed(() => store.categoryList)

//鼠标进入修改响应式数据currentIndex属性
const changeIndex = throttle((index: number) => {
    currentIndex.value = index
}, 50)

//一级分类鼠标移进的事件
const enterShow = () => {
    if (route.path !== '/home') {
        show.value = true
    }
}

//一级分类鼠标移出的事件
const leaveShow = () => {
    //鼠标移出currentIndex变为-1
    currentIndex.value = -1
    if (route.path !== '/home') {
        //隐藏三级联动菜单
        show.value = false
    }
}

//去搜索页面
const goSearch = (e: Event) => {
    //存在一些问题，事件委派，是把全部的子节点【h3、dt、dl、em】的事件委派给父亲节点
    //点击a标签的时候，才会进行路由跳转【怎么确定点击的一定是a标签】
    let element = e.target as HTMLDivElement
    let {categoryname, category1id, category2id, category3id} = element.dataset
    //如果标签身上拥有categoryname一定是a标签
    if (categoryname) {
        //准备路由跳转的参数
        let location: RouteLocationNamedRaw = {name: 'search'}
        let query: LocationQueryRaw = {categoryName: categoryname}
        if (category1id) {
            query.category1Id = category1id
        } else if (category2id) {
            query.category2Id = category2id
        } else {
            query.category3Id = category3id
        }
        if (route.params) {
            location.params = route.params
            location.query = query
            router.push(location)
        }
    }
}

onMounted(() => {
    //当组件挂载完毕，让show(显示三级联动菜单)属性变为false
    //如果不是home组件，将TypeNav隐藏
    if (route.path !== '/home') {
        show.value = false
    }
})
</script>

<style scoped lang="less">
.type-nav {
    border-bottom: 2px solid #e1251b;

    .container {
        width: 1200px;
        margin: 0 auto;
        display: flex;
        position: relative;

        .all {
            width: 210px;
            height: 45px;
            background-color: #e1251b;
            line-height: 45px;
            text-align: center;
            color: #fff;
            font-size: 14px;
            font-weight: bold;
        }

        .nav {
            a {
                height: 45px;
                margin: 0 22px;
                line-height: 45px;
                font-size: 16px;
                color: #333;
            }
        }

        .sort {
            position: absolute;
            left: 0;
            top: 45px;
            width: 210px;
            height: 461px;
            background: #fafafa;
            z-index: 999;

            a {
                cursor: pointer;
            }

            .all-sort-list2 {
                .item {
                    h3 {
                        line-height: 30px;
                        font-size: 14px;
                        font-weight: 400;
                        overflow: hidden;
                        padding: 0 20px;
                        margin: 0;

                        a {
                            color: #333;
                        }
                    }

                    .item-list {
                        display: none;
                        position: absolute;
                        width: 734px;
                        min-height: 460px;
                        background: #f7f7f7;
                        left: 210px;
                        border: 1px solid #ddd;
                        top: 0;
                        z-index: 9999 !important;

                        .subitem {
                            float: left;
                            width: 650px;
                            padding: 0 4px 0 8px;

                            dl {
                                border-top: 1px solid #eee;
                                padding: 6px 0;
                                overflow: hidden;
                                zoom: 1;

                                &.fore {
                                    border-top: 0;
                                }

                                dt {
                                    float: left;
                                    width: 54px;
                                    line-height: 22px;
                                    text-align: right;
                                    padding: 3px 6px 0 0;
                                    font-weight: 700;
                                }

                                dd {
                                    float: left;
                                    width: 415px;
                                    padding: 3px 0 0;
                                    overflow: hidden;

                                    em {
                                        float: left;
                                        height: 14px;
                                        line-height: 14px;
                                        padding: 0 8px;
                                        margin-top: 5px;
                                        border-left: 1px solid #ccc;
                                    }
                                }
                            }
                        }
                    }
                }

                .cur {
                    background-color: skyblue;
                }
            }
        }

        //过渡动画的样式
        //开始状态
        .sort-enter-from,
        .sort-leave-to {
            height: 0;
        }

        .sort-enter-active {
            transition: all 0.3s;
        }
    }
}
</style>
